#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
int main()
{
	int a, b, c;
	while (scanf("%d %d %d", &a, &b, &c))
	{
		if ((a + b > c) && (a + c > b) && (b + c > a))
		{
			if (a == b && b == c)
				printf("Equilateral triangle!\n");
			 else if ((a == b && c != a) || (a == c && b != a) || (b == c && a != b))
				printf("Isosceles triangle!\n");
			else
				printf("Ordinary triangle!\n");
		}
		else
			printf("Not a triangle!\n");
	}
	return 0;
}